Honestly, that part is one of the few areas where I agree with Dick. If we could get, say, half the violence off TV that we have now and maybe learn to start resolving conflicts in non-violent ways more often, and do more to help those with mental issues, it's quite likely there'd be a drop in shootings.
There would also be a large drop in shootings if we could get poverty shrinking rather than growing.
You know, work on eliminating the things that make people want to commit murder.
But maybe you Brits are right and it's the guns MAKING Americans kill each other.